Date: Wed, 27 Jul 2005 02:11:32 GMT From: "James Sweet" <jamessweetnospamail.com> Subject: Re: 1982 900 crankshaft pulley source?
> > The crank pulley, or harmonic balancer, consists of two pieces of steel > - an inner disk and an outer ring - with a rubber band sandwitched > between them. > > As the rubber ages, it is no longer capable of transmitting full torque > to the outer ring, so you get slippage between inner disk (driven by the > crankshaft) and outer ring (which drives the belts). > > The symptoms usually start with a squeal on startup, and on revving etc. > Similar to belt squeal. This gradually gets worse, until the pulley > eventially comes apart. > > A good way to keep an eye on it: using white marker, draw a couple of > lines on the outer surface of the pulley (the face you can see), running > from the center to the outer edge. These lines cross the rubber band. If > you ever get slippage, the lines will no longer line up. A quick glance > at the pulley at service time will tell you if there's been any slippage. > > Ah, that makes sense, didn't realize the belts were driven through the harmonic ballancer.